Dropper assemblies are not new per se. A typical construction is shown in Mitchell U.S. Pat. No. 3,154,116. The assembly illustrated therein comprises a blow-molded one-piece medicine dropper unit including an elongated dropper tube or barrel 10 made of a rigid material and is integrally formed with a collapsible bellows 12. The dropper is supported on the discharge end of a container such as a bottle by a cap having a radially inwardly directed flange portion in its top which engages at the lower end of the bellows. The prior art also discloses push and turn cap assemblies. See for example, Hedgewick U.S. Pat. Nos. 3,485,403 and 3,756,445 and Powers U.S. Pat. No. 3,200,979 entitled LATCHING CAP issued Aug. 17, 1965. In the assemblies illustrated, particularly the Hedgewick Patents, the cap is normally biased axially in one direction by spring means, part of which is formed integrally with the cap in Hedgewick U.S. Pat. No. 3,485,403 and is a separable element which cooperates with the cap in Hedgewick U.S. Pat. No. 3,756,445.